[909mustangx2]

Hey guys just finished swapping a 2002 4.6 into my 98 gt. Should it feel a little sluggish? Seems like after shifting into a gear it takes a min to pick up? Maybe the clucth? Theres no check engine lights or anything! Do I need a tune due to the differnet fuel and air ratio? Im still using my 98 gt computer! Anyone have some info for me?

Thanks

Overall the swap went good...engine running good and everything hooked up correctly! Any ideals? Will not having a tune after a swap yeld these sluggish results?

[ReverendDexter]

Give the MAF a good cleaning, and seafoam it (through the vacuum system).

Also, triple check all your grounds, and add an extra one from the block to the chassis for good measure.

[909mustangx2]

thanks revenerenddexter....ok ill check those tommorow! Could it be a clucth problem also? Anybody else have any input?

[ReverendDexter]

Originally Posted by 909mustangx2 thanks revenerenddexter....ok ill check those tommorow! Could it be a clucth problem also? Anybody else have any input?

I don't *think* it'd be the clutch; if the clutch was slipping you'd see the rpm coming up but you wouldn't be going any faster... kinda like just lightly pulsing the gas pedal in an automatic.

This sounds more like a stumble to me, does it do it when you hold rpms at a certain point, say cruising at 2500, and then punch it?

[909mustangx2]

Originally Posted by ReverendDexter I don't *think* it'd be the clutch; if the clutch was slipping you'd see the rpm coming up but you wouldn't be going any faster... kinda like just lightly pulsing the gas pedal in an automatic. This sounds more like a stumble to me, does it do it when you hold rpms at a certain point, say cruising at 2500, and then punch it?

exactly.... when crusing and i punch it it stumbles and slowly picks up speed...

[909mustangx2]

anyone else have anything to add to this problem? Got off work late so i couldnt check it today but first thing in the morning? Will it act like this if the block isnt grounded?

Or could it be my 98 gt ecu still is programed for the old fuel and air ratio from my old 98 gt motor and my new 2002 motor is pi?

[330CubeGt]

Mabye to much Fuel and or Air.
IDK Could Be Many things.

[2002BLGT]

ok , now I understand why you post in both sections , get some NGK iridiums , stock heat range , just tell the parts store guys to give you NGK iridium plugs for the 98 , dont run the TR6s , they are too cold for all motor , get some good Bosch replacment wires from Autozone , they have alot less resistance than most OEM wiresets ..... and I can get you the tuning done when you are ready to buy a kit , just have to change the timing tables for the 99-04 model engine , I have done alot of PI swap cars like yours ......the tuning makes a pretty big difference ......probably more than you think it will , the air/fuel is probably just a little rich , they are just like that with the stock tune , you are still running the 98 MAF right ?

[909mustangx2]

yes im still using the 98 mas air flow sensor, should i be using a 2002 mass air flow sensor...


also in 2 weeks i will be ordering my sniper....

[ReverendDexter]

Originally Posted by 2002BLGT ok , now I understand why you post in both sections , get some NGK iridiums , stock heat range , just tell the parts store guys to give you NGK iridium plugs for the 98 , dont run the TR6s , they are too cold for all motor , get some good Bosch replacment wires from Autozone , they have alot less resistance than most OEM wiresets ..... and I can get you the tuning done when you are ready to buy a kit , just have to change the timing tables for the 99-04 model engine , I have done alot of PI swap cars like yours ......the tuning makes a pretty big difference ......probably more than you think it will , the air/fuel is probably just a little rich , they are just like that with the stock tune , you are still running the 98 MAF right ?

Really? Bosch wires? I'd rather go to sparkplugs.com and pick up either an NGK or Denso wireset, but that's me. In my brief stint slinging parts, I never heard *anything* good about Bosch *anything* other than their 02 sensors and high end wiperblades.

[2002BLGT]

Originally Posted by ReverendDexter Really? Bosch wires? I'd rather go to sparkplugs.com and pick up either an NGK or Denso wireset, but that's me. In my brief stint slinging parts, I never heard *anything* good about Bosch *anything* other than their 02 sensors and high end wiperblades.

Ive been in parts business for over 10 years , hook up a ohm meter and check resistance on any brand wire and then compare it to the Bosch , they have about a tenth of the resistance per foot compared to any other wire out there ....